In this cytogenetic study the progeny of all crosses were investigated in F1, F2 and backcross (BC1) hybrids. Brassica napus and F1 hybrids between B. napus and B. oleracea, and between B. napus and three wild relatives of B. oleracea (B. bourgeaui, B. cretica and B. montana). Each of the wild relatives has 18 somatic chromosomes. Interspecific F1 hybrids were obtained through ovary culture mean. These had 28 and 37 chromosomes and their mean pollen fertility was 10.7% and 93.0%, respectively. Many F2 and BC1 seeds were harvested from the F1 hybrids with 37 chromosomes after self-pollination and open pollination of the F1 hybrids, and backcrossing with B. napus. Many aneuploids were obtained in the F2 and BC1 plants. It is evident from these investigations that the F1 hybrids may serve as bridge plants to improve B. napus and other Brassica crops.